Tetra-coordinated boron derivatives, (EtO)B(DTZ) and (DTZH)B(DTZ), (where DTZ⁻⁻ and DTZ⁻ represent the anions of the Schiff base DTZH₂) have been synthesized by 1:1 and 1:2 molar reactions of triethoxyborane with bibasic tridentate Schiff bases, derived by the equimolar condensation of S-methyl or S-benzyldithiocarbazate with acetyl acetone or benzoyl acetone. Further 1:1 derivatives have been shown to undergo replacement reactions witht-butyl alcohol, showing thereby the labile nature of the ethoxy group. Based on infrared and proton magnetic resonance spectral studies and monomeric nature, suitable structures have been assigned to these derivatives.

Reactions of tin(IV) chloride with Schiff bases having ONN donor systems have been investigated and on the basis of elemental analysis, IR, PMR and¹¹⁹Sn Mössbauer spectral studies, possible structures have been indicated for the resulting new compounds. The Schiff bases used in these studies are the condensation products of salicylaldehyde with sulphathiazole, sulphaphenazole, sulphadiazine, sulphaguanidine, 2-(p-aminobenzene sulphonamide)-4,5-dimethyl oxazole, sulphisoxazole, sulphapyridine and sulphanilamide.

Different molar reactions of Fe(OPr¹)₃, and FeCl₃ with benzothiazolines having an NSH donor system. derived by the condensation ofo-aminothiophenol with heterocyclic aldehydes. viz. pyridine-2-aldehyde. furfuraldehyde and thiophene-2-aldehyde. lead to the formation of [Fe.Pr¹(NS)₂]₂, [Fc(NS)₃] and [Fe(NS)₂Cl¦ type of complexes. The resulting derivatives have been characterized by elemental analysis, conductivity measurements, molecular weight determinations and magnetic studies. IR, electronic, Mössbauer and ESR spectral data have been used to deduce the structures of the resulting derivatives.